In many types of commercial art used in advertisements, sales brochures and the like, a message or statement may be highlighted with a border. In many situations involving commercial art, hundreds of line borders may be drawn daily in providing the master set-up. These line borders can be done by hand by use of a straight edge and ink pen or pencil and a curved template. However, it is extremely difficult to provide a continuous uniform line in passing from a first line through a rounded corner into a second line of a border. Often times at the speed which is required to turn out many borders per day in commercial art, the lines do not always exactly meet and non-uniformity in the design results. Furthermore, when it is desired to draw several concentric borders consisting of parallel lines with rounded corners at their intersection, it becomes increasingly difficult to provide a uniform attractive configuration.
Many drawing instruments and devices have been developed to provide for the drawing of parallel lines or uniformly spaced curved lines. Most commercial devices require the rotation of a guide device when drawing curved corners which interconnect intersecting lines. Examples of these types of devices are found in U.S. Pat. Nos. 2,509,164, 2,561,585, 3,465,445 and 4,335,515. Normally if a curved corner is desired, then the template which the drawing instrument guide follows has a correspondingly rounded portion in the manner disclosed in U.S. Pat. No. 4,335,515. U.S. Pat. No. 2,509,164 discloses the drawing of rounded corners between intersecting lines. However, the guide must rotate as the drawing instrument draws the rounded corner between the intersecting lines defined by the rulers. A similar device is disclosed in U.S. Pat. No. 3,465,445. The difficulty with the guides rotating during the drawing of corner portions, and for that matter with rotating during other sequences in drawing of lines, is that due to frictional engagement, vibrations can be induced in the drawing instrument resulting in jagged edges for the line and a non-uniform appearance.
Attempts have been made to smooth out the rotation of guide devices, such as disclosed in U.S. Pat. No. 2,782,506 where the drawing instrument is mounted in a bearing device which minimizes the effect of rotation of the device as it follows a guide. However, this arrangement is complex in design and far too involved for the simple technique of drawing line borders. Another device, which may or may not involve rotary heads, is disclosed in U.S. Pat. No. 3,867,761. The templates for guiding the end of the drawing device may be telescoped within a single unit. Depending upon which concentric ring abuts the template, the positioning of the line relative to the template is determined to provide for a multi-line border. However, this system is bulky and difficult to use in maintaining uniform lines because of possible slippage of one or more of the spring loaded concentric rings off of the template.